X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from omr-m01.mx.aol.com ([64.12.143.75] verified) by logan.com (CommuniGate Pro SMTP 6.0.5) with ESMTP id 6331154 for lml@lancaironline.net; Tue, 18 Jun 2013 12:41:51 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.143.75; envelope-from=Sky2high@aol.com Received: from mtaomg-da05.r1000.mx.aol.com (mtaomg-da05.r1000.mx.aol.com [172.29.51.141]) by omr-m01.mx.aol.com (Outbound Mail Relay) with ESMTP id 35B497000009A for ; Tue, 18 Jun 2013 12:41:16 -0400 (EDT) Received: from core-mta005a.r1000.mail.aol.com (core-mta005.r1000.mail.aol.com [172.29.234.145]) by mtaomg-da05.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 06908E000090 for ; Tue, 18 Jun 2013 12:41:16 -0400 (EDT) From: Sky2high@aol.com Full-name: Sky2high Message-ID: Date: Tue, 18 Jun 2013 12:41:15 -0400 (EDT) Subject: Re: [LML] Re: Propeller choice for Lancair 320 and Back Plate failures To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_daa93.2d285f3f.3ef1e7ab_boundary" X-Mailer: AOL 9.6 sub 168 X-Originating-IP: [67.175.156.123] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1371573676; bh=DxN0y5iT5rN4TeXOPw+ouTn+dVCt0wbe7ztqEBSc6jA=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=Jot5v/mhzYOn11zf3e3nH7fPvRPhbeYoW5ocb+XYvnk6CCt2UPWg0sxTz3ZhAwDqF 3wCNN1vylD/xBzkGz+qYVqsrtyyC93GMnbfLP3SCtH8wPEP84I+utQDaTi7kkxMYM1 AyvGHvRJg047F0qgi8Ga4V/FY/718OvsDH9HPA6Q= X-AOL-SCOLL-SCORE: 0:2:502642752:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d338d51c08dac1563 --part1_daa93.2d285f3f.3ef1e7ab_boundary Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Content-Language: en To all, =20 The most common reason that spinner back plates fail is because there is no= =20 bulkhead supporting the forward 1/3 of the spinner eliminating wobble. In= =20 Hartzell CS props, the bulkhead is usually bolted to the most forward end = =20 of the prop. =20 Bulkhead present =3D spinner not likely to fail. =20 No bulkhead =3D spinner subject to vibration and imbalance that can lead to= =20 failure. =20 Grayhawk =20 =20 In a message dated 6/18/2013 11:33:06 A.M. Central Daylight Time, =20 n5zq@verizon.net writes: =20 Hi Nick, =20 I have an MT two blade on our 320. We=E2=80=99ve got just under 2,200 hour= s on it=20 with no cracks in the blade or spinner parts. Our performance with the MT= =20 seems to be comparable to our friends with Hartzell props. I=E2=80=99m qu= ite happy=20 with the MT although I=E2=80=99m not sure that your information about it b= eing=20 lower cost is correct. You can purchase various blade lengths for either t= he=20 Hartzell or the MT.=20 =20 Bill Harrelson N5ZQ 320 2,150 hrs N6ZQ IV 300 hrs =20 =20 =20 =20 =20 From: _Nick Long_ (mailto:nick@beaglepup.info) =20 Sent: Tuesday, June 18, 2013 10:51 AM To: _lml@lancaironline.net_ (mailto:lml@lancaironline.net) =20 Subject: [LML] Propeller choice for Lancair 320 =20 =20 =20 =20 Hello Everyone, =20 With the discussion on MT backplates, this my be a good time to introduce = =20 myself and ask for the group=E2=80=99s opinion on something. =20 I have a Lancair 320 and I need a new prop. There=E2=80=99s no point beat= ing=20 about the bush: the reason is that I did a bad landing and had a prop stri= ke. =20 The engine is a Lycoming IO-320-B1A (ex Twin Comanche) and the current =20 propeller is a Hartzell 2 blade. It seems that some people are using the MT= 3 =20 blade instead, so I want to consider this as an alternative. =20 As far as I understand it, the MT prop is a little lower cost, it is =20 significantly lower weight, and it is 3 inches smaller diameter. On the fac= e of=20 it, all these things sound good. On the other hand, I have had people =20 telling me that they always seem to need new blades at overhaul time =E2=80= =93 they =20 develop cracks at the blade root. What I haven=E2=80=99t had anyone tell me= is what the=20 performance difference might be. In theory, a smaller diameter means less = =20 thrust, but the difference could easily be outweighed by design difference= s. =20 What does the group think? Has anyone experience of switching from one to = =20 the other? =20 Thanks, =20 Nick Long =20 =20 =20 =20 From: _Silvio Novelli_ (mailto:ppxsn@novellisouza.com.br) =20 Sent: Tuesday, June 18, 2013 1:37 PM To: _lml@lancaironline.net_ (mailto:lml@lancaironline.net) =20 Subject: [LML] Re: MT Spinner backing plate =20 No problems with mine, three blades Lyc IO 320, 100 hours. =20 Silvio Novelli Lancair 320 PP-XSN +55 (14) 9614-3129 =20 On 18 Jun 2013,w 25, at 8:45 AM, Dan Ballin wrote: =20 =20 =20 =20 Just wondering if anyone else has had this issue. I noticed cracks (3 of them) in the spinner backing plate of my=20 counterweighted MT prop for my Legacy. I have been keeping an eye on it b= ecause=20 Ralph Love has had two plates crack on him. I have had the prop about a y= ear,=20 it was dynamically balanced. Of interest both Ralph and I have Performance= =20 engines that have been inspected and altered ie bad parts out good parts = =20 in. Dan LEG2 N386DM --part1_daa93.2d285f3f.3ef1e7ab_boundary Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Content-Language: en
To all,
 
The most common reason that spinner back plates fail is because there = is no=20 bulkhead supporting the forward 1/3 of the spinner eliminating wobble. = ; In=20 Hartzell CS props, the bulkhead is usually bolted to the most forward = end=20 of the prop.
 
Bulkhead present =3D spinner not likely to fail.
 
No bulkhead =3D spinner subject to vibration and imbalance that can le= ad to=20 failure.
 
Grayhawk
 
In a message dated 6/18/2013 11:33:06 A.M. Central Daylight Time,=20 n5zq@verizon.net writes:
=
Hi Nick,
 
I have an MT two blade on our 320. We=E2= =80=99ve got=20 just under 2,200 hours on it with no cracks in the blade or spinner parts= . Our=20 performance with the MT seems to be comparable to our friends with Hartze= ll=20 props.  I=E2=80=99m quite happy with the MT although I=E2=80=99m not= sure that your=20 information about it being lower cost is correct. You can purchase variou= s=20 blade lengths for either the Hartzell or the MT.
 
Bill Harrelson
N5ZQ 320 2,150 hrs
N6ZQ  IV 300 hrs
 
 
 
From: Ni= ck=20 Long
Sent: Tuesday, June 18, 2013 10:51 AM
Subject: [LML] Propeller choice for Lancair 320
 
Hello Everyone,
 
With the discussion on MT backplates, this my be a good time to intr= oduce=20 myself and ask for the group=E2=80=99s opinion on something.
 
I have a Lancair 320 and I need a new  prop. There=E2=80=99s no= point=20 beating about the bush: the reason is that I did a bad landing and had a = prop=20 strike.
 
The engine is a Lycoming IO-320-B1A (ex Twin Comanche) and the curre= nt=20 propeller is a Hartzell 2 blade. It seems that some people are using the = MT 3=20 blade instead, so I want to consider this as an alternative.
 
As far as I understand it, the MT prop is a little lower cost, it is= =20 significantly lower weight, and it is 3 inches smaller diameter. On the f= ace=20 of it, all these things sound good. On the other hand, I have had people= =20 telling me that they always seem to need new blades at overhaul time =E2= =80=93 they=20 develop cracks at the blade root. What I haven=E2=80=99t had anyone tell = me is what=20 the performance difference might be. In theory, a smaller diameter means = less=20 thrust, but the difference could easily be outweighed by design=20 differences.
 
What does the group think? Has anyone experience of switching from o= ne to=20 the other?
 
Thanks,
 
Nick Long
 
 
From: Silvio Novelli
Sent: Tuesday, June 18, 2013 1:37 PM
Subject: [LML] Re: MT Spinner backing plate
 
= No=20 problems with mine, three blades Lyc IO 320, 100 hours.

     Silvio Novelli
Lancair 320=20 PP-XSN
+55 (14)=20 9614-3129
 

 
On 18  Jun 2013,w 25, at 8:45 AM, Dan Ballin wrote:
 
Just wondering if anyone else has had this issue.
I noticed= =20 cracks (3 of them) in the spinner backing plate of my counterweighted MT = prop=20 for my Legacy.  I have been keeping an eye on it because Ralph Love = has=20 had two plates crack on him.  I have had the prop about a year, it w= as=20 dynamically balanced. Of interest both Ralph and I have Performance engin= es=20 that have been inspected and altered ie bad parts out good parts=20 in.

Dan
LEG2  N386DM
 
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